Railroad crossing

ABSTRACT

The present invention relates to a railroad crossing ( 2 ). The railroad crossing ( 2 ) includes a railroad ( 4 ) along which a train can travel. The railroad crossing ( 2 ) further includes a road ( 6 ) extending across the railroad ( 4 ) and along which a vehicle or automobile can travel. The road ( 6 ) includes a curved approach ( 8 ) to the railroad ( 4 ). The curved approach ( 8 ) is effective in encouraging a reduction in speed of the vehicle without seriously disrupting vehicle traffic flow. The railroad crossing ( 2 ) further includes a movable vehicle impact barrier ( 10 ) which can prevent the vehicle from crossing the railroad ( 4 ). The road ( 6 ) may include two separated traffic lanes ( 16   a,    16   b ) in which vehicles travel in opposite directions, and this separation of the lanes ( 16 ) deters the vehicle from being driven from one lane  16   a  and into the other lane ( 16   b ) in an attempt to circumvent the barrier ( 10 ).

TECHNICAL FIELD

The present invention generally relates to a railroad crossing.

BACKGROUND

The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge.

A railroad crossing (also called a level crossing) is a crossing of a railroad by a road. Railroad crossings are often fitted with warning devices such as lights, bells and automatic boom gates to warn vehicles to give way to approaching trains. However, in spite of the existence of these warning devices, accidents at railway crossing remain a serious concern with many accidents continuing to occur because of a failure to notice or obey the warning devices. For example, vehicles are invariably driven around boom gates rather than waiting for them to be raised.

Many railroad crossings include a railroad and road which intersect at right angles. It can be difficult for speeding vehicles approaching these intersections to stop suddenly without entering the crossing. US 2008/0185482 discloses a railroad crossing in which the road includes an right-angled approach to the railroad to encourage a reduction in speed of an approaching vehicle. U.S. Pat. No. 1,571,166 discloses a railroad crossing in which the angled approach is advantageously less disruptive to general vehicle traffic flow than US 2008/0185482, although is less effective in encouraging a reduction in speed of the vehicle.

It is an object of the present invention to provide an alternative railroad crossing.

SUMMARY OF THE INVENTION

According to a first of the present invention; there is provided a railroad crossing including:

-   -   a railroad along which a train can travel;     -   a road crossing the railroad and along which a vehicle can         travel, the road including a curved approach to the railroad         which encourages a reduction in speed of the vehicle; and     -   a movable vehicle impact barrier for impeding the vehicle from         crossing the railroad.

The approach may include a curved wall. The wall may include visible markings to facilitate visual detection of the approach. The wall may include a concrete backing and cushion mounted to the backing to facilitate cushioning of the vehicle upon impact. The road may include two separated traffic lanes in which vehicles travel in opposite directions, one of the lanes including the approach which curves away from the other lane. The other lane may include another curved approach to the railroad. The approach may be generally s-shaped. Each lane may define a painted warning zone coincident with the railroad.

The crossing may further include a roundabout at an entrance to the curved approach. The crossing may further include a speed arrestor bed for retarding the speed of the vehicle entering the arrestor bed from the curved approach. The crossing may further include an upright wall adjacent the arrestor bed. The upright wall may include visible markings to facilitate visual detection of the arrestor bed. The upright wall may include a cushion to facilitate cushioning of the vehicle upon impact with the wall. The arrestor bed may include a pit filled with sand, gravel or other loose aggregate. The pit may increase in depth away from the curved approach. The crossing may further include an access road extending adjacent the arrestor bed. The crossing may further include a brightly painted road interconnection for interconnecting the curved approach and the arrestor bed.

The vehicle impact barrier may be arranged to deflect or guide the vehicle from the approach and into the arrestor bed. The barrier may include a pivotally mounted flipper which is able to pivot horizontally. The barrier may further include a locking mechanism for locking a free end of the flipper. The flipper may taper toward the free end.

Alternatively, the barrier may include retractable bollards. In another embodiment, the barrier may include a gantry to which an impact gate is pivotally mounted. The gate may be hollow and define internal webbing and corrugations for strengthening the gate. The gate may define an inclined impact face which is inclined from vertical when the gate acts as a barrier. In yet another embodiment, the barrier may include a pivotally mounted gate forming part of the road. In yet another embodiment, the barrier may include a pair of double gates.

The railroad crossing may include a control system for controlling the vehicle barrier. The control system may include:

-   -   a train sensor for sensing the train approaching the railroad         crossing along the railroad; and     -   a controller for controlling the barrier to impede the vehicle         from crossing the railroad subsequent to sensing the train         approaching the railroad crossing.

In one embodiment, the controller controls the barrier responsive to sensing the train approaching the railroad crossing. In another embodiment, the control system further includes a vehicle sensor for sensing the vehicle approaching the railroad crossing along the road and the controller controls the barrier responsive to sensing the approach of both the train and the vehicle approaching the railroad crossing.

The railroad crossing may further include a boom gate for extending across the road prior to the vehicle impact barrier, the boom gate being actuated by the controller responsive to sensing the train approaching the railroad crossing.

The control system may further include an electronic display for displaying a warning message to the vehicle. The control system may further include a vehicle speed sensor for sensing the approach speed of the vehicle along the road and the display may display another warning message responsive to detecting that the vehicle speed exceeds a predetermined threshold.

According to a second aspect of the present invention, there is provided a vehicle impact barrier for a railroad crossing, the barrier including a cantilevered arm which can pivot horizontally.

The barrier may further include a locking mechanism for locking a free end of the arm. The arm may taper both toward the free end and upwardly to define a sloping impact face.

According to a third aspect of the present invention, there is provided a railroad crossing including:

-   -   a railroad along which a train can travel;     -   a road crossing the railroad and along which a vehicle can         travel, the road including a curved approach to the railroad         which encourages a reduction in speed of the vehicle; and     -   a speed arrestor bed for retarding the speed of the vehicle         entering the arrestor bed from the curved approach.

According to a fourth aspect of the present invention, there is provided a method for displaying a warning message to a vehicle approaching a railroad crossing, the railroad crossing including a railroad along which a train can travel and a road crossing the railroad and along which the vehicle can travel, the method including the steps of:

-   -   sensing the train approaching the railroad crossing along the         railroad;     -   sensing the vehicle approaching the railroad crossing along the         road; and     -   displaying the warning message to the vehicle subsequent to         sensing both the train and the vehicle.

Between the steps of sensing and the step of displaying, the method may further include the step of determining a risk of a collision between the train and vehicle. The displayed warning message may be determined in accordance with the determined risk. The risk may be determined using the speed of the vehicle. The risk may be further determined using the speed of the train. The displayed message may be personalized to include a number plate indicator of the vehicle.

Prior to the step of displaying, the method may further involve the step of identifying the vehicle wherein the risk is determined in accordance with the identity of the vehicle. The risk may be determined in accordance with a behavioral profile of the vehicle.

Subsequent to the steps of sensing, the method may further include the step of moving a vehicle impact barrier to impede the vehicle from crossing the railroad.

The method may further include the step of actuating boom gates responsive to sensing the train approaching the railroad crossing.

The method may further include the step of sensing the vehicle has entered a speed arrestor bed. The method may further include the step of sending a status message relating to the status of the crossing. The status message may include an alarm signal advising that a vehicle has entered the speed arrestor bed.

According to a fifth aspect of the present invention, there is provided a system for a railroad crossing, the railroad crossing including a railroad along which a train can travel and a road crossing the railroad and along which the vehicle can travel, the system configured to:

-   -   sense the train approaching the railroad crossing along the         railroad;     -   sense the vehicle approaching the railroad crossing along the         road; and     -   display a warning message to the vehicle subsequent to sensing         both the train and the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:

FIG. 1 is a plan view of a railroad crossing in accordance with an embodiment of the present invention;

FIG. 2 a is a plan view showing a vehicle impact barrier of the railroad crossing of FIG. 1, the barrier being in an open configuration;

FIG. 2 b is a plan view showing the vehicle impact barrier of FIG. 2 a in a closed configuration;

FIG. 3 is a schematic drawing of a control system of the railroad crossing of FIG. 1;

FIG. 4 a is a side view showing a vehicle impatt barrier in accordance with another embodiment of the present invention, the impact barrier being in a non-obstructive configuration;

FIG. 4 b is a side view showing the vehicle impact barrier of FIG. 4 a in an obstructive configuration;

FIG. 5 a is a side view showing a vehicle impact barrier in accordance with another embodiment of the present invention, the impact barrier being in an obstructive configuration;

FIG. 5 b is a side view showing the vehicle impact barrier of FIG. 4 a in a non-obstructive configuration;

FIG. 6 is a side sectional view of a gate of the impact barrier of FIG. 5; and

FIG. 7 is a flowchart for a method of displaying a warning message to a vehicle approaching the railroad crossing of FIG. 1.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

According to an embodiment of the present invention, there is provided a railroad crossing 2 as shown in FIG. 1. The railroad crossing 2 includes a railroad 4 along which a train can travel. The railroad crossing 2 further includes a road 6 crossing the railroad 4 and along which a vehicle or automobile can travel. The road 6 includes a curved approach 8 to the railroad 4. The curved approach 8 is effective in encouraging a reduction in speed of the vehicle by the driver without seriously disrupting vehicle traffic flow. The railroad crossing 2 further includes a movable vehicle impact barrier 10 which can sustain vehicle impact and prevent the vehicle from crossing the railroad 4. A detailed description of the railroad crossing 2 is provided below.

As can best be seen in FIG. 2, the approach 8 includes a pair of curved walls 12 a, 12 b through which a lane 16 of the road 6 passes. The outer wall 12 b of the approach 8 includes visible markings to facilitate visual detection of the approach 8. The outer wall 12 b includes a concrete backing 14 and a cushion 16 mounted to the backing 14 to facilitate cushioning of the vehicle upon impact.

Returning to FIG. 1, the road 6 includes two separated traffic lanes 16 a, 16 b in which vehicles travel in opposite directions (shown by arrows). The separation of the lanes 16 deters the vehicle from being driven from one lane 16 a and into the other lane 16 b in an attempt to circumvent the barrier 10.

One of the lanes 16 a includes the approach 8 which curves away from the other lane 16 b. The other lane 16 b includes another curved approach to the railroad 4 and the crossing 2 further includes a roundabout 18 at an entrance to the other curved approach. Each curved approach 8 is generally s-shaped and each lane 16 defines a brightly painted warning zone 20 coincident with the railroad 4.

The crossing 2 further includes a speed arrestor bed 22 for retarding the speed of the vehicle entering the arrestor bed 22 from the curved approach 8. As can best be seen in FIG. 2, an upright wall 24 extends adjacent the arrestor bed 22 and includes visible markings to facilitate visual detection of the arrestor bed 22. The upright wall 24 can include a cushion to facilitate cushioning of the vehicle upon impact with the wall 24. The arrestor bed 22 includes a pit 26 filled with sand, gravel or other loose aggregate. The pit 26 increases in depth away from the curved approach 8 thereby increasing retardation of speed of the vehicle.

Returning to FIG. 1, the crossing 2 further includes an access road 28 extending from the curved approach 8 and adjacent the arrestor bed 22. A towing vehicle can travel along the access road 28 to gain access to a vehicle located in the arrestor bed 22. The crossing 2 further includes a brightly painted road interconnection 30 for interconnecting the curved approach 8 and the arrestor bed 22.

Returning to FIG. 2, the barrier 10 is arranged to deflect or guide the vehicle from the approach 8 and into the arrestor bed 22 upon impact. The barrier 10 includes a pivotally mounted flipper 32 (or cantilevered arm) which is able to pivot horizontally from the open configuration of FIG. 2 a to the closed configuration of FIG. 2 b, and visa versa. The barrier 10 further includes a pivotally mounted locking mechanism 34 for firmly locking a free end of the flipper 32. The flipper 32 tapers both toward its free end, and upwardly to define a sloping impact face.

Turning now to FIG. 3, the railroad crossing 2 includes a control system 36 for controlling the vehicle barrier 10. The control system 36 includes a train sensor 31 located on the railroad 4 for sensing the train approaching the railroad crossing 2 along the railroad 4. The train sensor 31 is positioned at a predetermined location on the railroad 4, so that the sensor 31 is triggered at a predetermined time before the train reaches the crossing based upon the mandated approach speed (i.e. speed limit) of the train through the crossing 2. The train sensor 31 may sense the train by detecting a short circuit between tracks at the predetermined location.

A controller 38 is provided for controlling the barrier 10 to prevent the vehicle from crossing the railroad 4 responsive to sensing the train approaching the railroad crossing 2. The controller 38 contains a software product 40 in resident memory. In turn, the software product 40 contains computer readable instructions for execution by a processor 42 of the controller 38 to control the barrier 10 and perform other tasks indicated below. The processor 42 is interfaced to a storage device (e.g. hard disc) containing a database 37 which includes, among other data relating to the control system 36, behavioral profiles relating to vehicles which regularly travel along the road 6. Each behavioral profile can be used in determining a risk of a collision between the train and the associated vehicle. The database 37 also includes a number of possible messages to be displayed to the vehicle based upon corresponding determined risk, with the severity of the messages increasing with risk of collision.

The control system 36 further includes a train speed sensor 29 coupled to the controller 38 and for sensing the speed of the train approaching the railroad crossing 2 along the railroad 4. The control system 36 further includes an arrestor bed sensor 33 coupled to the controller 38 and for sensing when the vehicle has entered the speed arrestor bed 22. The arrestor bed sensor 33 can include a pressure plate sensor or a beam sensor. In addition, the control system 36 further includes a road camera 35 for capturing images of the vehicle approaching the railroad crossing 2 along the road 6.

The railroad crossing 2 further includes boom gates 44 for extending across the road prior to each vehicle impact barrier 10 (see FIG. 1). The boom gates 44 are actuated by the controller 38 responsive to sensing the train approaching the railroad crossing 2. The control system 36 further includes an electronic display 46 located adjacent the road 6 and for displaying a warning message (e.g. CROSSING AHEAD) to the vehicle. In addition, the control system 36 further includes a vehicle speed sensor 48 for sensing the approach speed of the vehicle along the road 6. The speed sensor 48 can be connected to the controller 38 either via a wireless RF link or via a cable. The controller 38 can configure the display 46 to display another sterner warning message of increased severity (e.g. DANGER—SLOW DOWN) responsive to detecting that the vehicle speed exceeds a predetermined threshold and that the vehicle is likely to collide with the train.

The control system 36 further includes a RF transceiver 49 coupled to the controller 38 and for sending a status message relating to the status of the crossing 2 to a railroad monitoring facility. In addition, the status message may include an alarm signal advising that the vehicle has entered the speed arrestor bed 22 and can be sent to a emergency service facility (e.g. police, ambulance, etc).

Typically, the vehicle enters the curved approach 8 to the railroad 4 and is encouraged to slow down. The controller 38 closes the barriers 10 and lowers the boom gates 44 to prevent the vehicle from crossing the railroad 4 responsive to sensing the train approaching the railroad crossing 2.

In the event that the vehicle does not or cannot stop before reaching the crossing 2, the vehicle is prevented from crossing the railroad 4. In this manner, the vehicle may initially impact upon the curved wall 12 b, the barrier 10 spanning the lane 16 and then the arrestor bed wall 24 when traveling along the road 6, the road interconnection 30 and the arrestor bed 22. The boom gates 44, which effectively form a visual deterrent only, are not able to typically sustain the vehicle impact and may be destroyed.

A person skilled in the art will appreciate that many embodiments and variations can be made without departing from the ambit of the present invention.

For example, the barrier 10 and walls 12, 24 may include a variety of different materials including steel, concrete or any other like high strength material.

In another embodiment shown in FIG. 4, the barrier 10 includes a pivotally mounted gate 50 forming part of the road 6. The barrier 10 includes an actuator 52 controlled by controller 38 for pivoting the gate 50 from a non-obstructive configuration (FIG. 4 a) to an obstructive configuration (FIG. 4 b), and visa versa. In practice, the actuator 52 is located within a cavity 54 beneath the road 6.

In yet another embodiment shown in FIG. 5, the barrier 10 includes a gantry 60 to which an impact gate 62 is pivotally mounted. The barrier 10 includes an actuator controlled by controller 38 for pivoting the gate 62 from an obstructive configuration (FIG. 5 a) to a non-obstructive configuration (FIG. 5 b), and visa versa. Turning to FIG. 6, the gate 62 is hollow and defines internal webbing 64 and corrugations 66 for strengthening the gate 62. The gate 62 defines an inclined impact face 68 which is inclined from vertical when in the obstructive configuration (FIG. 5 a).

In yet another embodiment, the barrier 10 may include a pair of double swinging gates. In yet another embodiment, the barrier 10 can include retractable bollards positioned across the road 6.

In the preferred embodiments described above, controller 38 controlled the barrier 10 to impede the vehicle from crossing the railroad 4 subsequent to sensing the train approaching the railroad crossing 2. In another embodiment, the control system 38 further includes a vehicle sensor 70 (FIG. 3) for sensing the vehicle approaching the railroad crossing 2 along the road 6. The vehicle sensor 70 is positioned at a predetermined location on the road 6, so that the sensor 70 is triggered at a predetermined time before the vehicle reaches the crossing 2 based upon the mandated approach speed (i.e. speed limit) of the vehicle through the crossing 2. The vehicle sensor 70 can be connected to the controller 38 either via a wireless RF link or via a cable. The controller 38 is configured to control the barrier 10 responsive to sensing the approach of both the train and the vehicle approaching the railroad crossing 2.

FIG. 7 shows a method 80 for displaying a warning message to a vehicle approaching the railroad crossing 2.

At step 82, the controller 38 interfaced to train sensor 31 senses the train approaching the railroad crossing 2 along the railroad 4. The controller 38 actuates the boom gates 44 and moves the vehicle impact barrier 10 to impede the vehicle from crossing the railroad 4 responsive to sensing the train approaching the crossing 2.

At step 84, the controller 38 interfaced to vehicle sensor 70 senses the vehicle approaching the railroad crossing 2 along the road 6. The controller 38 also captures an image of the vehicle with road camera 35 responsive to sensing the vehicle approaching the crossing 2.

At step 86, the controller 38 identifies the vehicle by performing image processing of the captured image to electronically determine the vehicle's number plate.

At step 88, the controller 38 determines a risk of a collision between the train and the identified vehicle. The risk is determined using any one or more of: the speed of the vehicle sensed with the vehicle speed sensor 48, the speed of the train sensed with the train speed sensor 29 and the determined identity of the vehicle which corresponds with a behavioral profile of the vehicle stored in database 37. In one embodiment, the risk relates to the likelihood that the vehicle and train will be simultaneously co-incident on the crossing 2 based upon their sensed speeds. The risk may be determined using fuzzy logic, expert systems or other like adaptive control techniques. The displayed message is personalised to include an indicator of the vehicles number plate.

At step 90, the controller 38 determines a warning message to be displayed to the vehicle on display 46 based upon the determined risk. As previously discussed, the database 37 includes a number of possible messages to be displayed to the vehicle based upon corresponding determined risk, with the severity of the messages increasing with risk. The controller 38 then displays the determined warning on display 46.

At step 92, the controller 38 interfaced to arrestor bed sensor 33 senses the vehicle has entered the speed arrestor bed 22.

At step 94, the controller 38 interfaced to transceiver 49 sends the status message relating to the status of the crossing 2 to both the railroad monitoring facility and the emergency service facility. The status message includes the alarm signal advising that the vehicle has entered the speed arrestor bed 22.

In one embodiment, the controller 38 dynamically estimates the train and vehicle arrival times at the crossing 2 using the positions and speeds of the train and vehicle. The risk of a collision between train and vehicle can be determined in accordance with the difference between the estimated vehicle and train arrival times as indicated in the table below.

|vehicle arrival time − risk train arrival time| warning message Low >30 seconds CROSSING AHEAD Medium 15 to 30 seconds DANGER - SLOW DOWN High <15 seconds COLLISION IMMINENT

The controller 38 can select a warning message to display based upon the determined risk from the possible warning messages stored in the internal database 37 as indicated in the table above.

In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art. 

1. A railroad crossing including: a railroad along which a train can travel; a road crossing the railroad and along which a vehicle can travel, the road including a curved approach to the railroad which encourages a reduction in speed of the vehicle; and a movable vehicle impact barrier for impeding the vehicle from crossing the railroad.
 2. A railroad crossing as claimed in claim 1, further including a speed arrestor bed for retarding the speed of the vehicle entering the arrestor bed from the curved approach.
 3. A railroad crossing as claimed in claim 2, wherein the vehicle impact barrier is arranged to deflect or guide the vehicle from the approach and into the arrestor bed.
 4. A railroad crossing as claimed in claim 2, further including a wall adjacent the arrestor bed.
 5. A railroad crossing as claimed in claim 4, wherein the wall includes a cushion to facilitate cushioning of the vehicle upon impact with the wall.
 6. A railroad crossing as claimed in claim 2, wherein the arrestor bed includes a pit filled with sand, gravel or like loose aggregate, the pit increasing in depth away from the curved approach.
 7. A railroad crossing as claimed in claim 2, further including an access road extending adjacent the arrestor bed.
 8. A railroad crossing as claimed in claim 2, further including a brightly painted road interconnection for interconnecting the curved approach and the arrestor bed.
 9. A railroad crossing as claimed in claim 1, wherein the barrier includes a pivotally mounted flipper which is able to pivot horizontally.
 10. A railroad crossing as claimed in claim 9, wherein the barrier further includes a locking mechanism for locking a free end of the flipper.
 11. A railroad crossing as claimed in claim 1, wherein the barrier includes any one of retractable bollards, a gantry to which an impact gate is pivotally mounted, a pivotally mounted gate forming part of the road, and a pair of double gates.
 12. A railroad crossing as claimed in claim 1, wherein the approach includes a curved wall with visible markings to facilitate visual detection of the approach.
 13. A railroad crossing as claimed in claim 12, wherein the wall includes a concrete backing and cushion mounted to the backing to facilitate cushioning of the vehicle upon impact.
 14. A railroad crossing as claimed in claim 1, wherein the road includes two separated traffic lanes in which vehicles travel in opposite directions, one of the lanes including the approach which curves away from the other lane.
 15. A railroad crossing as claimed in claim 14, wherein the other lane includes another curved approach to the railroad.
 16. A railroad crossing as claimed in claim 1, wherein the approach is generally s-shaped and the crossing further includes a roundabout.
 17. A railroad crossing as claimed in claim 1, further including a control system for controlling the vehicle barrier, the control system including: a train sensor for sensing the train approaching the railroad crossing along the railroad; and a controller for controlling the barrier to impede the vehicle from crossing the railroad subsequent to sensing the train approaching the railroad crossing.
 18. A railroad crossing as claimed in claim 17, further including a boom gate for extending across the road prior to the vehicle impact barrier, the boom gate being actuated by the controller responsive to sensing the train approaching the railroad crossing.
 19. A railroad crossing as claimed in claim 17, wherein the control system further includes an electronic display for displaying a warning message to the vehicle.
 20. A vehicle impact barrier for a railroad crossing, the barrier including a cantilevered arm which can pivot horizontally.
 21. A railroad crossing including: a railroad along which a train can travel; a road crossing the railroad and along which a vehicle can travel, the road including a curved approach to the railroad which encourages a reduction in speed of the vehicle; and a speed arrestor bed for retarding the speed of the vehicle entering the arrestor bed from the curved approach.
 22. A method for displaying a warning message to a vehicle approaching a railroad crossing, the railroad crossing including a railroad along which a train can travel and a road crossing the railroad and along which the vehicle can travel, the method including the steps of : sensing the train approaching the railroad crossing along the railroad; sensing the vehicle approaching the railroad crossing along the road; and displaying the warning message to the vehicle subsequent to sensing both the train and the vehicle.
 23. A system for a railroad crossing, the railroad crossing including a railroad along which a train can travel and a road crossing the railroad and along which the vehicle can travel, the system configured to: sense the train approaching the railroad crossing along the railroad; sense the vehicle approaching the railroad crossing along the road; and display a warning message to the vehicle subsequent to sensing both the train and the vehicle. 